The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the inventors hereof, to the extent the work is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted to be prior art against the present disclosure.
Small electronic devices, such as those intended for consumer use, frequently incorporate microcontroller units (MCUs) that handle low-level tasks such as analog-to-digital conversion or controlling elements of a display. Typically, software run by such MCUs is permanently stored within read-only memory (ROM) of the MCU. Updating such software typically requires return of the device to its manufacturer, or a field service visit, to replace the ROM or the entire MCU. If the software is stored in rewritable memory, it may be possible to update the software without physically replacing the memory, but return of the unit or a field service visit, or purchase by the consumer of an expensive programming unit, may still be required.